Lead isolator



D.15,1 97o M BARKER 3,548,365

M l LEAD ISOLATOR Filed sept. 9, 1968 i i sheetsheet 1 Dec. 15, 19701 R.G. BARKER 3,548,365

` A A LEAD IsoLAToR l Filed sepmga,4 lseaf l g sheets-sheet 2 UnitedStates Patent O U.S. Cl. 339-176 16 Claims ABSTRACT OF THE DISCLOSURE Aprinted circuit connector for connecting aplurality of coaxial cables toa printed circuit. The connector has a connector base supporting aseries of contact pairs arranged with the pairs of successive contactsin two parallel rows. Each contact has a tab with the tabs arranged intwo rows. A lead isolator extends longitudinally of and between the tworows of tabs and has a series of holes extending through it. A coaxialcable is in each hole With the leads of the cable isolated from eachother. These leads of each cable are connected to a different one of agiven pair of tabs. A molded casing is lock-molded about the leadisolator leads and connector base.

SUBJECT MATTER OF THE INVENTION The present invention relates to anelectrical connector and, in particular, to a connector that is adaptedto connect a plurality of coaxial electrical cables to a terminal, suchas a printed circuit terminal.

BACKGROUND OF THE INVENTION Printed circuits, especially those used incomputer apparatus, are frequently designed for use with coaxial cablesof comparably fragile design. For that reason and others, there is aneed for an improved connector -to which these fragile and exotic cablesmay be connected simply and without the likelihood of shorting or breakswithin the connector.

SUMMARY OF THE INVENTION It is therefore an object of the presentinvention to provide an improved connector designed especially for usein connecting a plurality of coaxial cables to a mating terminal. Afurther object of the present invention is to provide an improved,printed circuit connector especially useful in telephone and computercircuitry. A further object of the present invention is to provide animproved means of terminating a plurality of fragile coaxial cables inaligned relation and in such a manner as to minimize the likelihood ofdamage to the connection of the cable leads which might result fromapplication of inadvertent forces. A further object of the presentinvention is to provide an improved printed circuit connector that canwithstand substantial abuse and handling Without the likelihood ofbroken connections or shorts. In this connection, the present inventionprovides an effective means for isolating the ground wire from thecenter wire of a coaxial cable, and further isolates each coaxial cablefrom adjacent coaxial cables. The present invention also provides meansby which a printed circuit connector can be assembled together withcoaxial cables in a permanent assembly rapidly and inexpensively and ina manner which is not likely to cause subsequent defective operation ofthe circuit in which the connector is used. A further object of thepresent invention is to provide an improved connector which may be usedfor a wide variety of different circuits and assemblies, and which isSusceptible of incorporation in relatively small circuits.

In the present invention, there is provided a connector ice for an arrayof coaxial cables comprising a connector having a plurality of pairs ofconnective tabs arranged with one tab of each pair in a dilferent one oftwo rows. An elongated, dielectric lead isolator extends lengthwise ofand intermediate the rows one from the other. The lead isolator has aplurality of recesses or holes each adapted to receive the end of acoaxial cable and provides means for electrically connecting one lead ofeach coaxial cable to one tab of a pair and the other lead thereof tothe other tab of the same pair.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing objects and advantagesof the present invention will be more clearly understood when consideredin conjunction with the accompanying drawings in which:

FIG. 1 is a perspective, partially fragmented illustration of a printedcircuitl connector embodying the present invention;

FIG. 2 is a fragmentary elevation in partial crosssection of the side ofthe finished connector of FIG. 1 which is hidden;

FIG. 3 is a cross-sectional detail taken along the line 3-3 of FIG. l;and

FIG. 4 is a cross-sectional detail of a modification taken substantiallyalong Ithe same line of the connector as FIG. 3 is taken.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Ithe connector.

Referring first to the embodiment illustrated in FIGS. l to 3, there isshown a connector base 1 which may be formed of any suitable, moldedmaterial ordinarily used for making dielectric 'bodies of an electricalconnector. This material may, for example, comprise a diallylphthalateplastic. This connector base is of conventional design in arrangement.Within the connector base 1 are a series of conductor pairs 2a and 2b,which are preferably arranged in two parallel rows spaced apart one fromthe other. The conductor pairs 2a and 2b are each formed withconventional contacts 3a and 3b at one end and integrally formed tabs 4aand 4b at the other end. The contacts may be of any suitable,conventional design and may, for example, comprise cantilevered,bifurcated, resilient contacts that are adapted to engage insulatedcontacts of a mating component on a circuit board or the like. Theconductors 2a and 2b may be suitably molded within conventional recessesin the conductor base 1, with the contacts 3a and 3b arranged inrecesses 5a and 5b on opposite sides of a longitudinally extending slot6.

Preferably, a series of holes `7 extends downwardly from the uppersurface 8 of the contact base intermediate the tabs `4a: and 4b. Thelength of these holes 7 may vary with the holes being provided at leastin part to permit a better engagement with the plastic cover which ismolded over the tabs 4a and 4b.

Holes 9 extend through the connector base 1 to provide a means foraligning the connector base with locating pins or the like. A leadisolator 10 extends longitudinally of the connector base and is securedover and to the surface 8 of this connector base between the rows oftabs 4a and 4b. This lead isolator may be made of any suitable moldeddiielectric material including, for example, diallylphthalate plastic.Preferably, the lead isolator should be molded of a transparent materialto make assembly and welding of the individual coaxial leads to the rowsof tabls 4a, 4b easier. The lead isolator has generally an elongated,rectangular conguration providing a top wall 11, bottom wall 12 andopposite side walls 13 and 14. Each of the side walls 13 and 14 areprovided with a series of slots 15 parallel to one another that extendfrom the bottom wall 12 to the top wall 11. These slots 15 have a widthand depth and are spaced apart to receive successively the tabs 4bwithin the slots 15 on side wall 14, and the tabs 4a within the slots 15on side wall 13.

A series of holes 18 extend parallel to one another from the top wall 11through the bottom wall 12. These holes 18 are each located with theiraxes intermediate adjacent pairs of tabs. Holes 18 have a diametersufcient to receive the full diameter of the coaxial cables beingconnected to the connector and extend toward but short of the bottomwall 12. Each of the walls 13 and 14 are formed with slots 27 thatextend from the holes 18 to the outer wall. The slots are parallel toand intermediate slots 15, and extend approximately halfway from topwall bottom wall 12. The cables 21 are inserted in parallel into theholes 18 in longitudinal array with the conductive leads 22 and 23exposed. The center lead 22 of each cable 21, is passed from hole 18 andis bent outwardly and angularly through a slot 27 into electricalcontact with one of the tabs 4a to which it is suitably welded. Thedrain lead 23 is bent angularly from the outer insulating cover 26 ofthe coaxial cable at a distance spaced from the point at which the lead22 is exposed. The lead 23 extends angularly through a slot 27 in theopposite wall 14 of the isolator and is electrically connected orsoldered to the tab 4b, corresponding to the tab 4a to which the centerlead 22 of the same coaxial cable is connected.

The ends of the lead isolator are provided with holes through whichscrews 30 extend to lock the lead isolator to the connector base 1. Thelead isolator is also provided with a series of parallel recesses orslots 32 intermediate slots 15 extending from wall 13 to wall 14 in thebottom wall 12. The slots 32 allow the cover molding to ow under thelead insulator and thereby prevents it from lifting away from theconnector in the finished product. The cover 35 is made of a suitablemolding material, preferably vinyl. This cover 35 has side walls whichare parallel and no further apart than the side walls of the connectorbase. The cover molding 35 extends about the parallel cables 21 withportions of the molding extending into the slot 32 to form an integralunit.

In the embodiment illustrated in FIG. 4, parts not specificallydescribed may be similar in construction to corresponding components ofthe embodiments of FIGS. l to 3. In this arrangement, the elongated leadisolator 110 is formed with a series of through holes 118 that extendfrom the top wall 111 of the lead isolator to the bottom wall 112. Theholes 118 are each formed with shoulder sections 90 and 91 whichsuccessively reduce the size of the hole from a diameter sufficient toreceive the full diameter of the coaxial cable 121 at the upper end ofthe lead isolator, to a diameter intermediate the top and bottom walls111 and 112 of the lead isolator such as to receive only the diameter ofthe inner insulation of the cable in an intermediate segment, and alower tapered segment 93 adapted only to receive the center lead 122 ofthe coaxial cable. The center lead 122 of the coaxial cable extendsthrough the bottom wall 112 and outwardly toward a tab 102a to which itis soldered. A series of slots 127 are formed in side 114 of the leadisolator and extend from the top wall 111 partially toward the bottomwall 112. The slots each interconnect the outer surface of wall 114 witha hole 118. Parallel slots are formed in the surface 114 to receive thetabs 1021;. The other wall 113 of the lead isolator is smooth except forparallel slots adapted to receive the tabs 10211. The drain lead 123 ofeach cable extends through a slot 127 and is soldered or otherwiseconnected to tab 102b. A vinyl covering is integrally molded about thecoaxial cables 121 in facing engagement with the connector base 101 towhich it is secured by portions of the covering 135 which extend intoundercut portions 136.

What is claimed is:

1. A connector for multiple-cable connection comprising a connectorbase, a plurality of conductors having each a pair of conductive tabsarranged in said connector base with one tab of each pair in a dilferentone of two rows, an elongated dielectric lead isolator extendinglengthwise of and intermediate said rows isolating said rows one fromthe other said lead isolator including sides having means dielectricallyengaging said rows, said lead isolator having a plurality of holeshaving means for receiving individually the ends of coaxial cables andproviding means for electrically connecting one lead of said coaxialcable to one tab of a pair, and means defining a passage for receivingthe other lead thereof for connection to the other tab of said pair.

2. A connector as set forth in claim 1 including an insulating coverextending over and integrally engaging said lead isolator.

3. A connector as set forth in claim 2 wherein said means forelectrically connecting one lead of said coaxial cable to one tab of apair, and the other lead thereof to the other tab of said pair comprisesmeans forming a passage from one of said holes outwardly of said leadisolator to one side thereof and means forming a second passage fromsaid one hole outwardly to a second side of said lead isolator with twoleads of said coaxial cable extending respectively one through each ofsaid passages into electrical connection with different ones of saidtabs of a pair of tabs.

4. A connector as set forth in claim 3 wherein said lead isolator isformed with one of said passages extending over one side and the otherof said passages extending over an opposite side of said lead isolator.

5. A connector as set forth in claim 3 wherein said connector basecomprises yan elongated member of dielectric material with saidconductive tabs extending from one elongated side thereof in twoparallel rows, said conductors each having a contact with said contactsarranged in two parallel spaced rows on a second elongated side of saidconnector base.

6. A connector as set forth in claim 5 wherein said lead isolator ispositioned intermediate said two rows of tabs adjacent said oneelongated side, means forming undercuts on one side of said leadisolator facing said connector base and said insulating cover havingintegrally formed portions extending into said undercuts.

7. A connector as set forth in claim 5 with said lead isolator having aplurality of parallel slots within which said tabs are located.

8. A connector as set forth in claim 7 including means for locking saidlead isolator to said connector base.

9. A connector as set forth in claim 8 wherein said means formingpassages includes slots in said lead isolator extending from said holesthrough one side of said lead isolator.

10. A connector as set forth in claim 9 wherein said means formingpassages includes holes in said lead isolator each of narrower diameterand continuous with one of said holes for receiving said coaxial cable.

11. A connector for multiple-cable connection comprising a connectorbase, a plurality of conductors each having a pair of conductive tabsarranged in said connector base with one tab of each pair in a differentone of two rows, an elongated dielectric lead isolator extendinglengthwise of and intermediate said rows, isolating said rows one fromthe other, said lead isolator having a plurality of holes having meansfor receiving individually the ends of co-axial cables, said leadisolator also having means defining passages extending laterally withrespect to the length of said lead isolator and to each side thereof,said passages being dimensioned to receive ditferent leads of saidcable.

12. A connector as set forth in claim 11 wherein said lead isolator isformed with a plurality of slots, each dimensioned and positioned toreceive one of said conductive tabs.

13. A connector as set forth in claim 12 wherein said slots and saidpassages are staggered longitudinally with respect to the length of saidlead isolator.

14. A connector as set forth in claim 13 wherein said lead isolatorincludes top and bottom surfaces, said passages extending frorn the topsurface of said lead isolator and communicating with said means forreceiving cables, and said slots extending from the bottom surface ofsaid lead isolator.

15. A connector as set forth in claim 14 wherein said leads of saidco-axial cable partially extend lengthwise and adjacent to a sidesurface of said lead isolator and are in electrical connection withdifferent ones of said tabs.

:16. A connector as set forth in claim 11 wherein said rst and secondleads of said coaxial cable extend through said passages, with one ofthe leads located closer to said top surface of said lead isolator.

Palmateer, Pluggable Cable to Card Connector, IBM Technical DisclosureBulletin, vol. 5, No. 4, September 1962, p. 28.

Uberbacher, Multistage Through-Hole, IBM Technical Disclosure Bulletin,vol. l0, No. 7, December 1967, p. 882.

MARVIN A. CHAMPION, Primary Examiner L. J. STAAB, Assistant ExaminerU.S. Cl. X.R. 3 39-177

